Cardiogenic Shock

What Is Cardiogenic Shock?

Cardiogenic (kar-dee-oh-JE-nik) shock is a condition in which a
suddenly weakened heart isn't able to pump enough blood to meet the
body's needs. The condition is a medical emergency and is fatal if
not treated right away.

The most common cause of cardiogenic shock is damage to the
heart muscle from a severe heart attack.
However, not everyone who has a heart attack has cardiogenic shock.
In fact, on average, only about 7 percent of people who have heart
attacks develop the condition.

If cardiogenic shock does occur, it's very dangerous. When
people die from heart attacks in hospitals, cardiogenic shock is
the most common cause of death.

When a person is in shock (from any cause), not enough blood and
oxygen are reaching the body's organs. If shock lasts more than a
few minutes, the lack of oxygen starts to damage the body’s organs.
If shock isn't treated quickly, it can cause permanent organ damage
or death.

If you think that you or someone else is in shock, call 9–1–1
right away for emergency treatment. Prompt medical care can save
your life and prevent or limit damage to your body’s organs.

Outlook

In the past, almost no one survived cardiogenic shock. Now,
about half of the people who go into cardiogenic shock survive.
This is because of prompt recognition of symptoms and improved
treatments, such as medicines and devices. These treatments can
restore blood flow to the heart and help the heart pump better.

In some cases, devices that take over the pumping function of
the heart are used. Implanting these devices requires major
surgery.

Immediate Causes

This damage prevents the heart’s main pumping chamber, the left
ventricle (VEN-trih-kul), from working well. As a result, the heart
can't pump enough oxygen-rich blood to the rest of the body.

In about 3 percent of cardiogenic shock cases, the heart’s lower
right chamber, the right ventricle, doesn’t work well. This means
the heart can't properly pump blood to the lungs, where it picks up
oxygen to bring back to the heart and the rest of the body.

Without enough oxygen-rich blood reaching the body’s major
organs, many problems can occur. For example:

If organs don't get enough oxygen-rich blood, they won't work
well. Cells in the organs die, and the organs may never work well
again.

As some organs stop working, they may cause problems with other
bodily functions. This, in turn, can worsen shock. For example:

If the kidneys aren't working well, the levels of important
chemicals in the body change. This may cause the heart and other
muscles to become even weaker, limiting blood flow even more.

If the liver isn't working well, the body stops making proteins
that help the blood clot. This can lead to more bleeding if the
shock is due to blood loss.

How well the brain, kidneys, and other organs recover will
depend on how long a person is in shock. The less time a person is
in shock, the less damage will occur to the organs. This is another
reason why emergency treatment is so important.

Heart Attack

Plaque reduces blood flow to your heart muscle. It also makes it
more likely that blood clots will form in your arteries. Blood
clots can partially or completely block blood flow.

Conditions Caused by Heart Attack

Heart attacks can cause some serious heart conditions that can
lead to cardiogenic shock. One example is ventricular septal
rupture. This condition occurs if the wall that separates the
ventricles (the heart’s two lower chambers) breaks down.

The breakdown happens because cells in the wall have died due to
a heart attack. Without the wall to separate them, the ventricles
can’t pump properly.

Heart attacks also can cause papillary muscle infarction or
rupture. This condition occurs if the muscles that help anchor the
heart valves stop working or break because a heart attack cuts off
their blood supply. If this happens, blood doesn't flow correctly
between the heart’s chambers. This prevents the heart from pumping
properly.

If you or someone else is having these signs and symptoms, call
9–1–1 right away for emergency treatment. Prompt medical care can
save your life and prevent or limit organ damage.

How Is Cardiogenic Shock Diagnosed?

The first step in diagnosing cardiogenic shock is to identify
that a person is in shock. At that point, emergency treatment
should begin.

Once emergency treatment starts, doctors can look for the
specific cause of the shock. If the reason for the shock is that
the heart isn't pumping strongly enough, then the diagnosis is
cardiogenic shock.

Tests and Procedures To Diagnose Shock and Its Underlying
Causes

Blood Pressure Test

Medical personnel can use a simple blood pressure cuff and
stethoscope to check whether a person has very low blood pressure.
This is the most common sign of shock. A blood pressure test can be
done before the person goes to a hospital.

EKG (Electrocardiogram)

An EKG is a
simple test that detects and records the heart's electrical
activity. The test shows how fast the heart is beating and its
rhythm (steady or irregular).

An EKG also records the strength and timing of electrical
signals as they pass through each part of the heart. Doctors use
EKGs to diagnose severe heart attacks and
monitor the heart's condition.

Echocardiography

Echocardiography (echo)
uses sound waves to create a moving picture of the heart. The test
provides information about the size and shape of the heart and how
well the heart chambers and valves are working.

Echo also can identify areas of poor blood flow to the heart,
areas of heart muscle that aren't contracting normally, and
previous injury to the heart muscle caused by poor blood flow.

Cardiac Enzyme Test

When cells in the heart die, they release enzymes into the
blood. These enzymes are called markers or biomarkers. Measuring
these markers can show whether the heart is damaged and the extent
of the damage.

Dye that can be seen on an x-ray image is injected into the
bloodstream through the tip of the catheter. The dye lets the
doctor study the flow of blood through the heart and blood vessels
and see any blockages.

Blood Tests

Arterial blood gas measurement. For this test, a blood sample
is taken from an artery. The sample is used to measure oxygen,
carbon dioxide, and pH (acidity) levels in the blood. Certain
levels of these substances are associated with shock.

How Is Cardiogenic Shock Treated?

Cardiogenic shock is life threatening and requires emergency
medical treatment. The condition usually is diagnosed after a
person has been admitted to a hospital for a heart attack. If
the person isn't already in a hospital, emergency treatment can
start as soon as medical personnel arrive.

Sometimes both the shock and its cause are treated at the same
time. For example, doctors may quickly open a blocked blood vessel
that's damaging the heart. Often, this can get the patient out of
shock with little or no additional treatment.

Providing breathing support if needed. A ventilator might be used
to protect the airway and provide the patient with extra oxygen. A
ventilator is a machine that supports breathing.

Giving the patient fluids, including blood and blood products,
through a needle inserted in a vein (when the shock is due to blood
loss). This can help get more blood to major organs and the rest of
the body. This treatment usually isn’t used for cardiogenic shock
because the heart can't pump the blood that's already in the body.
Also, too much fluid is in the lungs, making it hard to
breathe.

Medicines

During and after emergency life support treatment, doctors will
try to find out what’s causing the shock. If the reason for the
shock is that the heart isn't pumping strongly enough, then the
diagnosis is cardiogenic shock.

Medical Devices

An intra-aortic balloon pump. This device is placed in the
aorta, the main blood vessel that carries blood from the heart to
the body. A balloon at the tip of the device is inflated and
deflated in a rhythm that matches the heart’s pumping rhythm. This
allows the weakened heart muscle to pump as much blood as it can,
which helps get more blood to vital organs, such as the brain and
kidneys.

A left ventricular
assist device (LVAD). This device is a battery-operated pump
that takes over part of the heart’s pumping action. An LVAD helps
the heart pump blood to the body. This device may be used if damage
to the left ventricle, the heart’s main pumping chamber, is causing
shock.

Heart
transplant. This type of surgery rarely is done during an
emergency situation like cardiogenic shock because of other
available options. Also, doctors need to do very careful testing to
make sure a patient will benefit from a heart transplant and to
find a matching heart from a donor. Still, in some cases, doctors
may recommend a transplant if they feel it's the best way to
improve a patient's chances of long-term survival.

Act in time. Know the warning signs
of a heart attack so you can act fast to get treatment. Many
heart attack victims wait 2 hours or more after their symptoms
begin before they seek medical help. Delays in treatment increase
the risk of complications and death.

If you think you're having a heart attack, call 9–1–1 for help.
Don't drive yourself or have friends or family drive you to the
hospital. Call an ambulance so that medical personnel can begin
life-saving treatment on the way to the emergency room.

Clinical Trials

The National Heart, Lung, and Blood Institute (NHLBI) is
strongly committed to supporting research aimed at preventing and
treating heart, lung, and blood diseases and conditions and sleep disorders.

NHLBI-supported research has led to many advances in medical
knowledge and care. For example, the NHLBI sponsored a study to
find out whether early treatment to open blocked coronary arteries
could reduce in-hospital deaths from cardiogenic shock.

Many more questions remain about heart diseases and conditions,
including cardiogenic shock. The NHLBI continues to support
research aimed at learning more about these diseases and
conditions.

Research often depends on the willingness of volunteers to take
part in clinical trials.
Clinical trials test new ways to prevent, diagnose, or treat
various diseases and conditions.

For example, new treatments for a disease or condition (such as
medicines, medical devices, surgeries, or procedures) are tested in
volunteers who have the illness. Testing shows whether a treatment
is safe and effective in humans before it is made available for
widespread use.

By taking part in a clinical trial, you can gain access to new
treatments before they’re widely available. You also will have the
support of a team of health care providers, who will likely monitor
your health closely. Even if you don’t directly benefit from the
results of a clinical trial, the information gathered can help
others and add to scientific knowledge.

If you volunteer for a clinical trial, the research will be
explained to you in detail. You’ll learn about treatments and tests
you may receive, and the benefits and risks they may pose. You’ll
also be given a chance to ask questions about the research. This
process is called informed consent.

If you agree to take part in the trial, you’ll be asked to sign
an informed consent form. This form is not a contract. You have the
right to withdraw from a study at any time, for any reason. Also,
you have the right to learn about new risks or findings that emerge
during the trial.

For more information about clinical trials related to
cardiogenic shock, talk with your doctor. You also can visit the
following Web sites to learn more about clinical research and to
search for clinical trials: